NBR rubber

General characteristics

The characteristics of NBR vulcanizates depend primarily on the acrylonitrile content of the nitrile rubber used and on the type and quantity of plasticizer. In general, however, it can be said that NBR vulcanizates have a good resistance to gasoline, oils and mineral greases, but are poorly resistant to aging. The resistance level of natural rubber can be achieved through the addition of reinforcing fillers.

• Impact resistance: from 10 to 50%;
• Elongation to breakage: from 100 to 700% and beyond;
• Resistance to low temperatures: between -10°C and -50°C;
• Electrical characteristics: given that nitrile rubber is to be considered a semi-conductor, its vulcanizates are not suitable for electrical insulation.;
• Gas permeability: significantly lower than the NR, IR, BR, SBR, EPM and EPDM vulcanizates;
• Resistance to ozone, aging and weather: poor, but better than natural rubber;
• Chemical resistance: notable for the saturated polymer chain.

Good resistance to:

• Aliphatic hydrocarbons such as propane, butane, and benzene and mineral oils and greases;
• Flame resistant hydraulic fluids of the HCF group;
• Silicone oils and greases;
• Water (particular types up to 100°C);
• Many diluted acids, bases, and saline solutions at room temperature.

Average resistance to:

• Fuels with a high aromatic content, such as super fuels;
• Hydraulic fluids of the HFA group.

Not resistant to:

• Aromatic hydrocarbons (benzene), chlorinated hydrocarbons (trichloroethylene) or polar solvents (acetone).

Fields of application

NBR vulcanizates are used wherever rubber articles with a high resistance to benzene or mineral oils are required. Articles for which these characteristics are often required include gaskets, membranes, tubes, cylinder coatings, conveyor belts for fatty foods, shoe soles, gloves, cable coatings, foam rubber, hard rubber coatings, and closures for cans.